Sound-producing device



April 14,v 1 925. 1,534,016

J. P. NORTHEY -soUND PRODUCING DEVICE rNva-Nma Patented Apr. 14, 1925.

PATENT oFFlcE.

JOHN P. NORTHEY, OF TRONTO, ONTARIO, CANADA.

SO'UND-PRODUCING DEVICE.

Application led June 5', 1922, Serial No. 565,099. Renewed September 12,1924.

ton reciprocating in the cylinder also provided with orices which, bythe reciprocation of the piston, are alternately moved into and out ofalinement with the orifices in the cylinder to produce a rapidsuccession of puffs of air. As ordinarily arranged, such devices, whenthe piston speed is constant, produce a note of a given pitch, and myobject is to so construct the device .that the pitch of thenote soundedmay be changed at will without changing the piston speed.

I attain my object by providing means for varying at will the relativeposition of' the piston 'and'cylinder so that the piston orifices comeinto co-operative relation- Y ship with the cylinder orifices adifferent number of times during each reciprocation of the piston. Asimple arrangement will be such that-co-operation may take p-lace oncefor each single stroke of the piston or once during each double stroke,thus giving notes an octave apart.

The invention is hereinafter more specifically described and isillustrated in the accompanying drawings in which Fig. l is a view,partly in elevation and partly in section, of the apparatus;

Fig. 2 is a diagrammatic view showing the relative positioning of thecylinder and piston to produce a-puii of air for each single stroke ofthe piston;

Figf?) is a similar view showing the rela tive positioning of thecylinder andpiston to produce a puli of air for each double stroke ofthe piston;

Fig. 4 is a sectional view of the cvlindrical sleeve operatingmechanism; and

Fig. 5 a cross sectional detail of part of the casing and the cylinderof the sleeve operating mechanism.

Inrthe drawings like numerals oi' reference indicate corresponding partsin the different figures.

l is a casing in which is mounted a' cylindrical sleeve 2 so that it maybe adjusted longitudinally of the casing; Preferably the wall of thecylinder is made comparatively thin and rims 3 are formed at each endhaving a suitable sliding bearing on the casing. The wall of thiscylinder has a series of sound producing orifices 4 formed therein,which will usually be spaced at equal distances apart. Within thecylinder a hollow piston 5 is adapted to reciprocate, this piston beingalso provided with sound producing orifices 6 adapted to be brought intoa-linement with the oriices in the cylinder by the reciprocaton of thepiston. y

The piston is provi-ded with an enlarged part 7 adapted to reciprocatein the part 8 of the casing, which forms a cylinder therefor. Theapertured part of the piston is preferably separated from the remainderot the piston'by the diaphragm 9. The open end of the pistoncommunicates with the horn 10 which is suitably secured to the end ofthe casing.

llVithin the casing is formed the chamber ll communicating with the airinlet 12. The sound is produced by the reciprocation of the piston,which causes its sound producing orifices to coincide at regularintervals with the orices of the cylinder 2, thus producing a series ofpuii's of air which occur at such intervals as to form a musical note.

The cylinder is ordinarily positioned relative to the piston, which hasa fixed travel so that the orifices coincide once for each single strokeof the piston. (See Fig. 2.) By shifting the position of the cylinder,however, the piston may be caused to bring its sound producing orificesinto alinement with the sound producing orifices of the cylinder onceduring each double stroke, that is, at the end of the stroke in onevdirection and the beginning of the strokel in the other direction asillustrated in Figs. l and 3. Thus, at will, the device may be adjustedto produce either a high note or a low note, or by intermediateadjustments to cause various modications in the sound emitted by theinstrument. Further, even it it be desired to set the device to emit onenote only for a given piston speed, there isfgreat advantage in havingthe cylinder longitudinally adjustable as it may thus be very accuratelyand easily adjusted to the piston after the device has been assembled.

The longitudinal adjustment otthe cylinder may be effected in variousways. Behind the diaphragm k9 the side walls of the cylinder may be ofopen construction, and this enables me to extend a roch 'sha'l't 13through the walls of the casing and through the open sides of thepiston. This rock shaft carries cam projections 14 which are adapted toengage in notches 15 formed in the sides ot slots 1G termed in thecylinder wall opposite sides.Y By operating this rock shaft the cylindermay be moved backwards or forwards as desired. This rock shaft will beoperated as hereinafter Vdescribed'.

The piston and casing areconstructedin the following manner to eil'cctthe reciprocation of the piston. The enlarged part 7 is formed on adiaphragm 17` on which is formed a Ysleeve 18 extending in the directionci' the cylinder 2 and closely fitting a. cylindrical bore formed in thecasing. A space 19 for the admission of air behind the outer part of thediaphragm 17 is thusV :toi-med. rllhis space communicates with theannularinlet chamber 20 with which communicates the air inlet 21supplied with air by any suitable means.

A series of ports 22 term the comnnmication between the inlet chamber20- and the. space 19. In the part 7 of the piston` is formed an annulargroove 23 withl which communicate a series of porte24 opening into thespace 19. An annular exhaust groove Q5 is also formed in the part 7 otthe piston nearer the outer end thanV the groove 2e. A chamber 26 isformed in the part tl of the casing, and with this space communicateannular grooves 27, and the first groove being an inlet groove for airin iront oi. (he piston, the groove 29 an inlet groove for the air`behind the piston. An intermediate groove'QS forms an outlet groovewhich communicates with the atmosphere by one or more holes 30.

The operation is as follows. `With the parte shown as in 1, air passestrom the inlet chamber 20to the space 19, thenc through the ports 24 theannular groovel 23 and the groove V29 into thechamber 2G and through thegroove 27 to act on the outer surface oit the'diaphragm. The air pressurej is thus the samefin front of and behind the diaphragm 17, but the.edective area against which the pressure in the chamber 19 operatesisvery much less than*l the effective area at the outer end of the part7 of the piston, and consequently the'piston is moved to the right. Thismovement, however, cuts oil communication between the annular groove 29and the space 19 and brings this same groove through the medium of theexhaustgroove 25 into communication with the exhaust groove 28 of thecasing. The pres sure against the outer'end of the piston at once `fallsto that of the atmosphere and the air pressure in the space 19 is thensutlieient to throw the piston to the left and back to the position inwhich there is tree coinmunication between the space 19 and the chamber26, thus reeestablishing the equality of pressure between the space 19and the space betweenrthe piston end and the end of the part 8 of theeasing. The piston therefore will continue. to `reciprocate as long asair pressure is supplied through the air inlet 2l. This arrangement, however, is old in the art and no claim is made thereto, substantially thesame arrangement being shown in my prior United States Pat` ent No.879190.V Y

Y The method of supplying air to the air inlet l2 for the production ofthe sound and to theV air inlet 21 for the reciprocation ot the pistonforms no part of the present invention and the supply ot' air may becontrolled in any suitable manner. Y

Io operate the sleeve 2 to effect the adjustment hereinbefore referredto, I employ control mechanism similar to that now employed ior thecontrolxof the air to the air inlets. 31 is a drum suitably mounted androtated in any suitable manner. Its periphery is provided with one ormore cam proliections 32 which are adapted to rock a ylever 33 suitably:tulcrumed on a stationary part. T his lever is adapted to engage thestem 34 oi a valve disk 35 slidable in the valve casing 36, the valvedisk being adapted to cn gage the valve seat 37 so as 1o normally closethe eoinnulnication between the air inlet 3S and the air outlet 39. Thevalve is normally held closed bythe coil spring 40 engaging the cap 41of the valve casing and the valve disk itself.

VBelow the valveseat exhaust ports 42 com municate with the interior oithe valve eas ing. The lower part 43 of the valve stem is oit' greaterdiameter than the upper part and serves as a piston valve to open andclose the ei-:haust ports. Then the valve disk 35 is raised, the exhaustports are closed. When the valve disk 35 is seated, there is treeVcommunication between the air outlet 39 and the exhaust ports.V The airoutlet 39 is connected by means of a pipe 44 with the interiorof thecylinder 45 in which 0perates the piston 46, the piston rod 47 being oflarge diameter so as to materially reduce Vthe effective area of therear side of the piston. Behind the piston a port 48 communicates withthe interior of the cylinder, this port Vopening through a pad 49 whichis selill) f in the fork :termed on the end oi the roch arm 5e securedto 'the rock shaft 13.

Y lit will` be noted that the part 61 ot the cylinder through which thesound producing orifices are formed is slightly less in diameter thanthe impertoratc portion and also has its diai'neter reduced slightlyadjacent its forward end, and the piston is also necessarily similarlyreduced. The piston and cylinder are also so proportioned that, whenthey are being assembled, the end ot the piston enters the part of thecylinder of least diameter at or about the time that the part ot thepiston ot slightly greater diameter' enters the part oic the cylinder otslightly greater` diameter.

Normally the valve disk is closed and the exhaust ports 42 open. Thereis then no pressure in front of the piston i6 owing to the communicationbetween the cylinder 45 and the air outlet 39. The pressure 'from theair chamber ll behind the piston lo will thus be suiiicient to press thepiston it@ over to thD right as shownin the drawings, thus moving thecylindrical sleeve 2 to its limit ofmotion in one direction. llVhen,however, the cam projection 32 on the drum 3l en- V gages and rocks thelever 33, the valve disl:

35 is raised and the exhaust ports-42 closed. Air pressure enteringthrough the air inlet 88 will thus pass through.l the valve casing 36,through the pipe 44 to the cylinder l5 and operating against'the frontend of the piston 46 Will push the latter to the lett as, though ytheair pressure behind and in trout is the saine.,` the greater effectivearea of the Yfront of the piston enables the air pressure in i'ront oitit to overcome the air pressure behind it The cylindrical sleeve 2 isthus pressed tothe limit of its moven'ient in the opposite direction.The two positions of thesleeve relative to the piston hereinbeforereferred to are thus automatically obtained.

In practice the drum 31 is used to effect the timing of the operation otadmitting air for the reciprccation of the `piston and the production otsound, and the timing oi the operation ot the piston 46 to shift theposition of the sleeve 2 may be set to cause the shift oit the positionat any desired time While the piston 5 is in motion so as to change thecharacter of the sound emitted as hereinbetore referred to.

It is evident, et course, that many other methods than that described:tor eiiecting the shift of the sleeve 2 Will tall Within the scope ofmy invention. It is 'further evident slidablc through a bracket 5l4 thatinde endently of the change inthe character of t ie note emittedthat thcinovability oi the sleeve enables me to accurately adjust its positionrelative to the piston in any case where it is desired that theinstrument shall be used tor the production ot one note only.

As the horn 10 acts not only as a sound concentrating and directingdevice, but also as a resonating chamber, it is ot the utmost importancethat it shall be propely proportioned relative to the note produced bythe operation ot the piston in the cylinder. lt is obvious that it it beci the proper size and proportions to sound one of the noteshereinbeiiore referred to, it Will not he ot the proper dimensions tosuit the other. l thereitore, as the notes Will usually be :n octaveapart, provide the hornintermediate of its length with a series ofapertures Which are adapted to be opened and closed by a ring 56, thisring, having openings therein which may be caused by the operation ofthe ring to open or close the apertures 55. This ring may be arranged tobe inovedin any suitable manner. l show it, however, as being adapted tohave an oscillating rotary movement a 1ound the horn. rIhis movementmust talre place synchronously with the movement of the sleeve 2. Thismovement may be effected in very many Ways. l shov.T it as being`effected b v means of a rock arm 5T secured to the shaft 13, this rockarm being pivotally connected with a connecting rodl 58 pivotallyconnected with a bell crank lever 59 suitably tulcrumed on the horn andhaving its end engaged with a iorlr 60 formed on the ring 56. The partsare so proportioned that the apertures 55 are open when the high note isbeing sounded and closed when the low note is being sounded,v theresonating lengt-h oi the horn being cut in halt when thc apertures areopen.

lt is, however, in many cases not essential that the entrance of theparts of the pistou et different diameters into the parts of thecylinder in which they have a Working tithe simultaneous and either onemay enter before the other. rlhe diiierencc in the diaineter is verf.'small and the small end ot the pist-on entering the part oil' thecylinder ot slightly larger diameter is thus guided in substantialparallelism With the cylinder so that the parts of the piston readilyenter the parts of the cylinder in which they have a Working fit.

lhat l claim as my invention is 1. A. pneumatic sound producing devicecomprising a cylinder having sound produc ingoriices in its Wall; apiston adapted to reciprocate in said cylinder having sound producingorifices adapted to be brought into alinement with the orifices in thecylinder by the reciprocation oi' the piston; and rmeans for varying therelative positions of the cylinder and piston to vary the number oftimes ,the said orifices are brought into cooperation during each doublestroke of the piston.

2. A pneumaticv sound producing device comprising a cylinder havingsound'producing orifices in its Wall; a piston adapted to reciprocate insaid cylinder having sound producing orifices adapted to be brought intoalinement with the orifices in the cylinder by the reciprocation of thepiston; and means for varying the relative positions of the cylinder andpiston axially thereof to Vary the number ofv times the said orificesare brought into co-operation during each double stroke of the piston.

3. A Apneumatic sound producing device comprising a cylinder havingsound producing orifices in its Wall; a piston adapted to reciprocate insaid cylinder having sound producing orifices adapted to be brought intoalinement with the orifices in the cylinder by the reciprocation of thepiston; and means for varying the relative positions of the cylinder and.piston axially thereof so that the reciprocation of the piston maybringV the orifices into co-operation either at the end of each strokeof the piston in one direction or intermediate the ends of' each stroke.

4:. A pneumatic sound producing device comprising a cylinder havingsound produc ing orifices in its Wall; a piston adapted to reoiirocatein said c dinder havinr sound l D producing orifices adapted to bebrought into alinement with the orifices in the cylinder by thereciprocation of the piston; `means for varying the relative positionsof the cylinder and piston to vary the number of times the said orificesare brought vinto co-operation during each double stroke of the piston;and a timing device adapted to automatically control said positionvarying means to change the relative position `of the cylinder andpiston at predetermined intervals.

5; A pneumatic sound producing device comprising a casing; a cylindersupported in said casing so as to be movable longitudinally of its axisand having sound producing orificesvformed in its- Wall; a hollow pistonopen at one end vadapted to reciprocate in said cylinder, said pistonhaving sound producing orifices formed in its Wall adapted to be broughtinto alinement with the orifices in the cylinder Wall; and means formoving'said cylinder.

6. A pneumatic sound producing device comprising a cylinder with soundproducing orifices in its Wall and an-annular enlargement at one endprovided with air ports; a cover for the cylinder; a hollow piston openat one end, having sound producing orifices adapted to co-operate withthe sound producing orifices of the cylinder and provided with anenlargement remote from the open end7 fitting the annular enlargement ofthe cylinder and ports in said enlargement cooperatng with the cylinderports to control the admission and exhaust of the air which effectsthereciprocation of the piston, the piston adjacent its open end beingslightly reduced in diameter and the cylinder correspondingly reduced indiameter and the parts proportioned so that when the piston and cylinderare being assembled the end of the piston enters the part of thecylinder of least diameter at or about the same time that theenlargement of the piston enters the annular enlargement of Vthecylinder; and a diaphragm in said piston close to -the innermostsoundeproducing orifices.

7. A pneumatic sound producing device comprising a cylinder having soundproducing orifices in its Wall; a piston adapted to reciprocate in saidcylinder `having sound producing orifices adapted to be brought intoalinement with the orifices in the cylinder by the reciprocation of thepiston; means for varying the relative positions of the cylinder andpiston to vary the number of times the said orifices are brought intocooperation during each double stroke of the' piston; a resonating horn;and means for varying the effective resonating length of the horn tocorrespond With the Ipitch of the sound produced and in synchronisrnwith the means for varying the relative position of the cylinder andpiston.

8. In a pneumatic sound producing device, the combination of an airmotor; two co-operating parts, one movable relative to the other by thevair motor, and adapted When supplied With yair under pressure to causeya rapid succession of puffs of air Vadapted to produce a musical note;means for varying the relationship of said parts to vary the pitchV ofthe note; a resonating horn; and meansfor simultaneously.changing theeffective resonating length of the horn to suit the pitch of the noteproduced.

9. A pneumatic sound producing device comprising a cylinder with soundproducing orifices in its Wall and an annular enlargement at one endprovided 'with air ports; a cover for the cylinder; a yhollow pistonopen at one end, having sound producing orifices adapted to co-operat'ewith the sound producing orifices of the cylinder and provided with anenlargement vremote from the open end, fitting the annular enlarge-Ament of the cylinder and ports in said enlargement cooperating with thecylinder ports to control the admission and exhaust of the air Whicheffects the reciprocation of the piston,the piston adjacent its open endbeing slightly reduced in diameter and the cylinder correspondinglyreduced in diameter and the parts proportioned so that vvhen the pistonand cylinder are being assembled the end of the piston enters the parliofl the cylinder of least diameter at or about the same time that thepart of the piston of normal diameter enters the end of the part of Ehecylinder Within which it has a Working 10. A pneumatic sound producingdevice including a cylinder having its forward part of slightly reduceddiameter and a piston similarly formed, the piston and cylinder alsobeing so proportioned that the end of the piston enters the part of thecylinder of least diameter at or about the time that the part of thepiston of normal diameter enters the end of the part of the cylinderWithin which it has a Working Vfit.

11.' A pneumatic sound producing` device of the type described includinga cylinder With sound producing orifices in its Walls and a hollowpiston also having sound producing orifices formed in its Wall adaptedto co-operate with the sound producing oriiices of the cylinder, thecuter ends of the `cylinder and piston being slightly reduced indiameter whereby, when the parts are being assembled, the part of thepiston of smaller diameter iii-st enters the part ci the cylinder ofslightly larger diameter and is thus guided so that the parts of thepiston enter the parte of the cylinderI in Which they have their Workingiit.

Signed at Toronto, Canada7 this 26 day of May 1922.

JOHN P. NORTHEY.

